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783 Posts
Discussion Starter #1
Basically Im having a problem with my speedometer/cruise not working. So far I replaced the rear speed sensor but that did not solve my problem. My speedo is not getting a signal from the ABS unit. I've checked the wires from the guage cluster (one brown & one brown/red wire) through the harness to the ABS unit itself. All wire have good continuity to the ABS connector and show no shorts to ground.

I went back and checked both wires from the front and rear sensors to make sure that both had a good connection to the ABS unit and found no issues. I back probed the rear sensor with the bike running on the stand and put it in gear. My meter is showing a change with speed. So I know that is not an issue with the rear sensor. I checked for anything at the back of the speedo with the bike running in gear and could not get any kinda of signal.

What I have come up with is that the ABS unit is not sending the speed signal to the gauge cluster. Has anyone heard of a problem like this? I suspect that the ABS unit is faulty internally and Im not ready to pony up the dough for a new one. I've seen some other posts on here about people tearing apart the ABS units.

I had an issue before all this started with my speedo intermittenly not working and I wonder if there might be a bad contact inside the ABS unit itself.

Thanks for the Help! :confused:
 

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Wrencher Extraordinaire
2005 K1200LT
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14,246 Posts
Stephen,


I looked the circuit over. There are electronics in the ABS as well as the instrument cluster. Could be loosing the signal in either place. I would repeat the check you did with the bike in gear and put the meter on the TA- and TAS wires (pins 6 & 7 at the cluster) coming from the ABS going to the Instrument cluster just to see if it can detect a signal there - may need an O'scope to do that.

I would not recommend tearing into the ABS unit. And a GPS (2610 for $350) is a lot cheaper than an ABS unit and will give you a very accurate speed as well as other goodies.

Good Luck
 

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Premium Member
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783 Posts
Discussion Starter #3
No speedo/ cruise operation

jzeiler said:
Stephen,


I looked the circuit over. There are electronics in the ABS as well as the instrument cluster. Could be loosing the signal in either place. I would repeat the check you did with the bike in gear and put the meter on the TA- and TAS wires (pins 6 & 7 at the cluster) coming from the ABS going to the Instrument cluster just to see if it can detect a signal there - may need an O'scope to do that.

I would not recommend tearing into the ABS unit. And a GPS (2610 for $350) is a lot cheaper than an ABS unit and will give you a very accurate speed as well as other goodies.

Good Luck
I have checked at the instrument cluster for any type of signal. I do get signal from the rear sensor to the ABS control unit. Nothing coming out, so I have come to the conclusion there is an open circuit there. This problem started with an intermittent loss of the speedo/cruise control operation. I see that the top of the ABS control unit could in theory be disassembled to some degree but I would rather not go there. I may be loading the bike up next week to see if a diagnostics check would show the problem.

I would love to have the GPS unit but I would sure miss the cruise control.
 
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